CVE-2021-40829 Vulnerability Analysis & Exploit Details

CVE-2021-40829
Vulnerability Scoring

6.3
/10
High Risk

If left unpatched, CVE-2021-40829 could lead to major system disruptions or data loss.

Attack Complexity Details

  • Attack Complexity: High
    Exploits require significant effort and special conditions.
  • Attack Vector: Adjacent_network
    Attack Vector Under Analysis
  • Privileges Required: High
    High-level privileges are required for exploitation.
  • Scope: Unchanged
    Exploit remains within the originally vulnerable component.
  • User Interaction: Required
    User interaction is necessary for successful exploitation.

CVE-2021-40829 Details

Status: Modified

Last updated: 🕕 21 Nov 2024, 06:24 UTC
Originally published on: 🕛 23 Nov 2021, 00:15 UTC

Time between publication and last update: 1094 days

CVSS Release: version 3

CVSS3 Source

cve-notifications-us@f-secure.com

CVSS3 Type

Secondary

CVSS3 Vector

CVSS:3.1/AV:A/AC:H/PR:H/UI:R/S:U/C:H/I:H/A:H

CVE-2021-40829 Vulnerability Summary

CVE-2021-40829: Connections initialized by the AWS IoT Device SDK v2 for Java (versions prior to 1.4.2), Python (versions prior to 1.6.1), C++ (versions prior to 1.12.7) and Node.js (versions prior to 1.5.3) did not verify server certificate hostname during TLS handshake when overriding Certificate Authorities (CA) in their trust stores on MacOS. This issue has been addressed in aws-c-io submodule versions 0.10.5 onward. This issue affects: Amazon Web Services AWS IoT Device SDK v2 for Java versions prior to 1.4.2 on macOS. Amazon Web Services AWS IoT Device SDK v2 for Python versions prior to 1.6.1 on macOS. Amazon Web Services AWS IoT Device SDK v2 for C++ versions prior to 1.12.7 on macOS. Amazon Web Services AWS IoT Device SDK v2 for Node.js versions prior to 1.5.3 on macOS. Amazon Web Services AWS-C-IO 0.10.4 on macOS.

Assessing the Risk of CVE-2021-40829

Access Complexity Graph

The exploitability of CVE-2021-40829 depends on two key factors: attack complexity (the level of effort required to execute an exploit) and privileges required (the access level an attacker needs).

Exploitability Analysis for CVE-2021-40829

The exploitability of CVE-2021-40829 is influenced by multiple factors. Security teams should analyze system configurations and apply appropriate countermeasures to mitigate threats.

Understanding AC and PR

A lower complexity and fewer privilege requirements make exploitation easier. Security teams should evaluate these aspects to determine the urgency of mitigation strategies, such as patch management and access control policies.

Attack Complexity (AC) measures the difficulty in executing an exploit. A high AC means that specific conditions must be met, making an attack more challenging, while a low AC means the vulnerability can be exploited with minimal effort.

Privileges Required (PR) determine the level of system access necessary for an attack. Vulnerabilities requiring no privileges are more accessible to attackers, whereas high privilege requirements limit exploitation to authorized users with elevated access.

CVSS Score Breakdown Chart

Above is the CVSS Sub-score Breakdown for CVE-2021-40829, illustrating how Base, Impact, and Exploitability factors combine to form the overall severity rating. A higher sub-score typically indicates a more severe or easier-to-exploit vulnerability.

CIA Impact Analysis

Below is the Impact Analysis for CVE-2021-40829, showing how Confidentiality, Integrity, and Availability might be affected if the vulnerability is exploited. Higher values usually signal greater potential damage.

  • Confidentiality: High
    Exploiting CVE-2021-40829 can result in unauthorized access to sensitive data, severely compromising data privacy.
  • Integrity: High
    CVE-2021-40829 could allow unauthorized modifications to data, potentially affecting system reliability and trust.
  • Availability: High
    CVE-2021-40829 can disrupt system operations, potentially causing complete denial of service (DoS).

Exploit Prediction Scoring System (EPSS)

The EPSS score estimates the probability that this vulnerability will be exploited in the near future.

EPSS Score: 0.109% (probability of exploit)

EPSS Percentile: 45.7% (lower percentile = lower relative risk)
This vulnerability is less risky than approximately 54.3% of others.

CVE-2021-40829 References

External References

CWE Common Weakness Enumeration

CWE-295

CAPEC Common Attack Pattern Enumeration and Classification

  • Creating a Rogue Certification Authority Certificate CAPEC-459 An adversary exploits a weakness resulting from using a hashing algorithm with weak collision resistance to generate certificate signing requests (CSR) that contain collision blocks in their "to be signed" parts. The adversary submits one CSR to be signed by a trusted certificate authority then uses the signed blob to make a second certificate appear signed by said certificate authority. Due to the hash collision, both certificates, though different, hash to the same value and so the signed blob works just as well in the second certificate. The net effect is that the adversary's second X.509 certificate, which the Certification Authority has never seen, is now signed and validated by that Certification Authority.
  • Signature Spoofing by Improper Validation CAPEC-475 An adversary exploits a cryptographic weakness in the signature verification algorithm implementation to generate a valid signature without knowing the key.

Vulnerable Configurations

  • cpe:2.3:o:apple:macos:-:*:*:*:*:*:*:*
    cpe:2.3:o:apple:macos:-:*:*:*:*:*:*:*

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